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991.
Stéphanie Blanchard Anthony D. William Angeline C.-H. Lee Anders Poulsen Ee Ling Teo Weiping Deng Noah Tu Evelyn Tan Kay Lin Goh Wai Chung Ong Chee Pang Ng Kee Chuan Goh Zahid Bonday Eric T. Sun 《Bioorganic & medicinal chemistry letters》2010,20(8):2443-2447
A series of alkenyl indazoles were synthesized and evaluated in Aurora kinase enzyme assays. Several promising leads were optimized for selectivity towards Aurora B. Excellent binding affinity and good selectivity were achieved with optimized compounds in isolated Aurora subfamily assays. 相似文献
992.
Jeffrey Y. Melamed Amy E. Zartman Nathan R. Kett Anthony L. Gotter Victor N. Uebele Duane R. Reiss Cindra L. Condra Christine Fandozzi Laura S. Lubbers Blake A. Rowe Georgia B. McGaughey Martin Henault Rino Stocco John J. Renger George D. Hartman Mark T. Bilodeau B. Wesley Trotter 《Bioorganic & medicinal chemistry letters》2010,20(15):4700-4703
Administration of Neuropeptide S (NPS) has been shown to produce arousal, that is, independent of novelty and to induce wakefulness by suppressing all stages of sleep, as demonstrated by EEG recordings in rat. Medicinal chemistry efforts have identified a quinolinone class of potent NPSR antagonists that readily cross the blood–brain barrier. We detail here optimization efforts resulting in the identification of a potent NPSR antagonist which dose-dependently and specifically inhibited 125I-NPS binding in the CNS when administered to rats. 相似文献
993.
Yohan Nigaud Pascal Cosette Anthony Collet Philippe Chan Tchi Song David Vaudry Hubert Vaudry Guy-Alain Junter Thierry Jouenne 《Biochimica et Biophysica Acta - Proteins and Proteomics》2010,1804(4):957-966
While recent studies focused on Quorum Sensing (QS) role in the cell-to-cell communication in free or biofilm cultures, no work has been devoted up to now to investigate the communication between sessile and planktonic bacteria. In this aim, we elaborated an original two-chambered bioreactor and used a proteomic approach to study the alterations induced by Pseudomonas aeruginosa biofilm cells on protein expression in planktonic counterparts (named SIPs for Surface-Influenced Planktonics). Proteomic analyses revealed the existence of 31 proteins whose amount varied in SIPs, among which five corresponded to hypothetic proteins and two (the Fur and BCP proteins) are involved in bacterial response to oxidative stress. An increase in the concentration of C4-HSL (rhlR–rhlI-dependent QS) and 3-oxo-C12-HSL (lasR–lasI-dependent QS) autoinducer molecules was shown in the planktonic compartment. Interestingly, among proteins that were accumulated by SIPs was 3-oxoacyl-[acyl-carrier-protein] reductase, a protein involved in the production of the autoinducer 3-oxo-C12-HSL. These results demonstrate that planktonic organisms are able to detect the presence of a biofilm in their close environment and to modify their gene expression in consequence. 相似文献
994.
Anthony M. Heagerty Egidius H. Heerkens Ashley S. Izzard 《Journal of cellular and molecular medicine》2010,14(5):1037-1043
It has been known for some considerable time that sustained hypertension changes the circulatory architecture both in the heart and blood vessels. The histopathological alterations are of considerable interest because once they have developed they appear to carry an adverse prognostic risk. In the heart it is apparent that there is hypertrophy. This extends also to the large- and medium-sized blood vessels but at the level of the smaller arteries that contribute to vascular resistance, this is not the case: it is clear that the physiological response to higher pressures is a change in the positional conformation of the pre-existing tissue constituents and as a result of this the lumen is narrowed. This brief review looks at our knowledge in this area and attempts to clarify our understanding of how hypertension brings these about and what happens when these homeostatic mechanisms break down. From a therapeutic perspective it appears imperative to control blood pressure in an attempt to reverse or prevent such alterations to cardiovascular structure. Our knowledge is fast expanding in this field and it is only to be anticipated that as detection methodology improves everyday practice will alter as we profile our patients in terms of structural alterations in the ventricle and blood vessels. 相似文献
995.
Gonzales DA De Torre C Wang H Devor CB Munson PJ Ying SX Kern SJ Petraitiene R Levens DL Walsh TJ Suffredini AF 《Proteomics》2010,10(23):4270-4280
We hypothesized that invasive pulmonary aspergillosis (IPA) may generate a distinctive proteomic signature in plasma and bronchoalveolar lavage (BAL). Proteins in plasma and BAL from two neutropenic rabbit models of IPA and Pseudomonas pneumonia were analyzed by SELDI-TOF MS. Hierarchical clustering analysis of plasma time course spectra demonstrated two clusters of peaks that were differentially regulated between IPA and Pseudomonas pneumonia (57 and 34 peaks, respectively, p<0.001). PCA of plasma proteins demonstrated a time-dependent separation of the two infections. A random forest analysis that ranked the top 30 spectral points distinguished between late Aspergillus and Pseudomonas pneumonias with 100% sensitivity and specificity. Based on spectral data analysis, three proteins were identified using SDS-PAGE and LC/MS and quantified using reverse phase arrays. Differences in the temporal sequence of plasma haptoglobin (p<0.001), apolipoprotein A1 (p<0.001) and transthyretin (p<0.038) were observed between IPA and Pseudomonas pneumonia, as was C-reactive protein (p<0.001). In summary, proteomic analysis of plasma and BAL proteins of experimental Aspergillus and Pseudomonas pneumonias demonstrates unique protein profiles with principal components and spectral regions that are shared in early infection and diverge at later stages of infection. Haptoglobin, apolipoprotein A1, transthyretin, and C-reactive protein are differentially expressed in these infections suggesting important contributions to host defense against IPA. 相似文献
996.
Michel Toussaint Anthony J. Olejniczak Pierre Cattelain Claire Letourneux 《Journal of human evolution》2010,58(1):56-67
A human lower right deciduous second molar was discovered in 1984 at the entrance of Trou de l'Abîme at Couvin (Belgium). In subsequent years the interpretation of this fossil remained difficult for various reasons: (1) the lack of taxonomically diagnostic elements which would support its attribution to either Homo (sapiens) neanderthalensis or H. s. sapiens; (2) the absence of any reliable chronostratigraphic interpretation of the sedimentary sequence of the site; (3) the contradiction between archaeological interpretations, which attributed the lithic industry to a transitional facies between the Middle and Early Upper Palaeolithic, and the radiocarbon date of 46,820 ± 3,290 BP obtained from animal bone remains associated with the tooth and the flint tools.Thanks to recent progress regarding these three aspects, the tooth from Trou de l'Abîme may now be studied in detail. Analyses of the morphology and enamel thickness of the fossil yielded diagnostic characters consistent with an attribution to Neandertals. Re-examination of the lithic industry of Couvin shows that it corresponds to the late Middle Palaeolithic rather than a transitional facies. Furthermore, a new analysis of the site stratigraphy indicates that the unit situated above the archaeological layer in which the tooth was found is probably a palaeosol of brown soil type. Comparison with the regional cave sequences as well as with the reference sequence from the Belgian loess belt tends to show that the most recent palaeosol of this type is dated between 42,000 and 40,000 BP. This is consistent with both a recently obtained AMS result at 44,500 BP and the published conventional date. 相似文献
997.
998.
I. Somboonwatthanaku S. Dorling S. Leung M. T. McManus 《Plant Cell, Tissue and Organ Culture》2010,103(3):369-376
The regulation of proline biosynthesis has been examined in callus and cell cultures of the indica-type rice cultivar Khao
Dawk Mali 105 (KDML105) in response to a saline treatment (250 mM NaCl) in terms of the expression of Δ1-pyrroline-5-carboxylate reductase (OsP5CR) and members of the gene family encoding the rate-determining enzyme, Δ1-pyrroline-5-carboxylate synthase (designated OsP5CS1 and OsP5CS2). Using friable callus, growth was retarded by treatment with 250 mM NaCl within 4 days, with a significant increase in the
expression of OsP5CS2 by 24 h, and a less marked induction in OsP5CS1 and OsP5CR over the same time-course. Cell suspension cultures derived from the friable callus were also treated with 250 mM NaCl and
an induction in OsP5CS2 was again observed, although this was not as marked as in the friable callus, and there was no significant change in OsP5CS1 and OsP5CR expression. This is the first report that details the expression of OsP5CS1 and OsP5CS2 in tissue culture and the results show that, in common with whole plants, OsP5CS2 displays a primacy of response to saline treatment. However, this response may require a community of communicating cells,
as occurs in callus tissue, rather than cell suspension cultures. This difference has implications both in terms of the biology
of signaling in response to increased salinity and in the use of tissue culture to screen for saline-tolerant germplasm. 相似文献
999.
1000.
The spider faunas of two savannah reserves along the eastern coastal plain of Africa are compared. Species richness was higher in the tropical area, with 493 species (54 families) from Mkomazi Game Reserve, Tanzania. Species richness was also high in the subtropics, with a total of 431 species (46 families) recorded from Ndumo Game Reserve, South Africa. Spider community structure was remarkably similar in the two reserves, with Salticidae, Gnaphosidae, Thomisidae, Theridiidae and Araneidae the most species‐rich families in both reserves. Eleven of the fourteen most species rich families were the same. A similar proportion of families were represented by singleton and doubleton species. A genus‐ and species‐level comparison of ten spider families indicates that while there is considerable overlap in the generic composition of the reserves (Sorensen’s Quotient of similarity: all >0.650 except Linyphiidae, 0.166; Corinnidae, 0.500) there is little overlap between the species occurring in the two sites (0.000–0.571), which was particularly evident in the more species‐rich families. A comparison of diversity of 57 families in each reserve with the spider biodiversity in the two sub‐regions suggests that local biodiversity is largely determined by regional biogeographical influences rather than local ecological factors. 相似文献